Eutectoid Transformation in Zn-Al Alloys Solidified by Rapid Cooling

Abstract:

Rapid solidification represents a very attractive approach to develop new Al alloys in an economically convenient way. The lower segregation content, refined grains, higher ultimate tensile and yield strengths combined to a good ductile properties confer to these materials an interesting position also in the so critical automotive and/or aeronautical applications. The current paper presents results of an analysis concerning Zn-Al alloys with a new metastable microcrystalline structure, where Copper has been used as alloying element. With addition of elements as Ti and B modification of the microstructure has been reached. In order to study the influence of the cooling rate on the microstructure and structural transformations castings has been realized with melt spinning technique, in both steel and sand moulds. For morphological investigations optical and scanning electron microscopy has been employed. By dilatometric analysis and X-Ray diffraction technique the thermodynamic factors, the kinetic effects, phase transformations and the volume changes related to the transformations produced at the eutectoid temperature have been monitored. For the aforementioned field of applications the most favourable composition has been chosen: based on the up to date outcomes, by modifying the original alloy with some elements a quite homogeneous structure combined with good mechanical behaviour has been obtained.

• Periodical: Materials Science Forum (Volumes 790-791)
• Pages: 223-228
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.790-791.223
• Online since: May 2014
• Authors: Ildiko Peter*, Béla Varga, Mario Rosso
• Keywords: Eutectoid Transformation, Metastable Structure, Rapid Solidification, Zn-Al Alloys

References

[1] H.V. Atkinson, D. Liu, Microstructural coarsening of semi-solid aluminium alloys, Materials Science and Engineering: A 496 1-2 25 (2008) 439-446.

DOI: 10.1016/j.msea.2008.06.013

[2] Kliauga, A.M., Liquid formation and microstructural evolution during re-heating and partial melting of an extruded A356 aluminium alloy, Acta Materialia 53 (2005) 345-356.

DOI: 10.1016/j.actamat.2004.09.030

[3] Y. Birol, Semisolid processing of near-eutectic and hypereutectic Al-Si-Cu alloys, Journal of Materials Science 43 10 (2008) 3577–3581.

DOI: 10.1007/s10853-008-2565-6

[4] I. Peter, M. Rosso, C. Bivol, Microstructure and mechanical behaviour of Al-based alloy obtained by liquid forging technique, Metallurgia International, Vol. XIV Special Issue 2 (2009)15-19.

[5] Z. Fan, Semisolid metal processing, International Materials Reviews 47/ 2 (2002) 49–85.

[6] M. Rosso, I. Peter, R. Villa, Effects of T5 and T6 heat treatments applied to Rheocast A356 parts for automotive applications, Journal of Solid State Phenomena 141-143 (2008) 237-242.

DOI: 10.4028/www.scientific.net/ssp.141-143.237

[7] J. Hirsch, T. Al-Samman, Superior light metals by texture engineering: Optimized aluminum and magnesium alloys for automotive applications, Acta Materialia 61 (2013) 818–843.

DOI: 10.1016/j.actamat.2012.10.044

[8] E. Tillova, E. Durinkova, M. Chapulova, Structural analysis of secondary AlZn10Si8Mg cast alloy, Acta Metallurgica Slovaca 17/1 (2011) 4-10.

[9] E. Tillova, E. Durinkova, M. Chapulova, Properties of recycled AlZn10Si8 cast alloy after annealing, Materials Engineering - Materiálové inžinierstvo 18 (2011) 1-7.

[10] M. Azadi, M.M. Shirazabad, Heat treatment effect on thermo-mechanical fatigue and low cycle fatigue behaviors of A356. 0 aluminum alloy, Materials and Design 45 (2013) 279–285.

DOI: 10.1016/j.matdes.2012.08.066

[11] I. Aguilera Luna, H. Mancha Molinar, M.J. Castro Román, J.C. Escobedo Bocardo, M. Herrera Trejo, Improvement of the tensile properties of an Al–Si–Cu–Mg aluminum industrial alloy by using multi stage solution heat treatments, Materials Science & Engineering A 561 (2013).

DOI: 10.1016/j.msea.2012.10.064

[12] M. Savas, S. Altintas, The microstructural control of cast and mechanical properties of zinc-aluminium alloys, J. Materials Science 28 (1993) 1775-1780.

DOI: 10.1007/bf00595744

[13] Y. H. Zhu, Phase transformations of eutectoid Zn-Al alloys, J. Materials Science, 36 (2001) 3973-3980.

[14] Y. H. Zhu, K. C. Chan, G. K. H. Pang, T. M. Yue, W. B. Lee, Structural Changes of α Phase in Furnace Cooled Eutectoid Zn-Al Based Alloy, J. Mater. Sci. Technol., 23/3 (2007) 347-352.

[15] X. L. Xu, Z. W. Yu, S. J. Ji, J. C. Sun, Z. K. Hei, Differential Scanning calorimetry and X-ray diffraction studies on aging behavior of Zn-Al alloys, Acta Metallurgica Sinica, 14/2, (2001) 109-114.

[16] G. Torres-Villasenor, E. Martinez-Flores, Hybrid materials based on Zn-Al, Metal, Ceramic and Polymeric Composites for various uses, Published online 20 July 2011 http: /www. intechopen. com/books/metal-ceramic-and-polymeric-composites-forvarious-uses/hibrid-materials-based-on zn-al-alloys.

DOI: 10.5772/17241

[17] Y Wang, J Zeng: Eutectoid transformation in Zn alloy with high Al contant, in Advanced Materials Resarch, 652-654 (2013) 1111-1114.

DOI: 10.4028/www.scientific.net/amr.652-654.1111

[18] Y.H. Zhu, General rule of phase decomposition in Zn-Al based alloys(II)-on effects of external stresses on phase transformation, Materials Transactions, 45/11 (2004) 3083-3097.

DOI: 10.2320/matertrans.45.3083

[19] A. Sandoval-Jmenez, J. Negrete, G. Torres-Villasenor, Phase transformations in the Zn-Al eutectoid alloy after quenching from the high temperature triclinic beta phase, Materials characterization, 61 (2010) 1286-1289.

DOI: 10.1016/j.matchar.2010.07.014

[20] H. J. Dorantes-Rosales, V. M. Lopez-Hirata, J. Moreno-Palmerin, N. Cayetano-Castro, M. L. Saucedo-Munoz, A. A. Torres Castillo, β' phase decomposition in Zn-22 mass % Al and Zn-22 mass % Al-2 mass % Cu alloys at room temperature, Materials Transactions, 48/10 (2007).

DOI: 10.2320/matertrans.mrp2007058

[21] WEI JianNing, SONG ShiHua, HU KongGang, XIE WeiJun, MA MingLiang, LI GenMei, HAN FuSheng, Influence of macroscopic graphite particulates on the damping properties of Zn-Al eutectoid alloy, Science in China Series G: Physics, Mechanics & Astronomy 52 (1) (2009).

DOI: 10.1007/s11433-009-0007-3

[22] B. Varga, I. Peter, Structural transformations in Zn-Al22 alloy solidified by ultra-rapid cooling, in Metalurgia International, XVII Special Issue 6 (2013) 9-12.

[23] I. Peter, B. Varga, M. Rosso: Dimensional stability analysis in Al-Si alloys, in Metalurgia International, XVI/4 (2011) 5-9.

[24] W. K. Krajewski, P. L. Zak, J. Orava, A. L. Greer, P.K. Krajewski, Structural stability of the high-aluminium zinc alloys modified with Ti addition, Archives of Foundry Engineering 12/1 (2012) 61-66.

DOI: 10.2478/v10266-012-0012-2

[25] B. Varga, I. Lichioiu, Method and installation for obtaining metastable structures of aluminium alloys, Bulletin of the Transilvania University of Brasov, Series I Engineering Sciences 4 53/1 (2011) 1-6.

[26] H. J. Dorantes-Rosales, V. M. Lopez-Hirata, J. L. Mendez-Velazquez, M. L. Saucedo-Munoz, D. Hernandez-Silva, Microstructure characterization of phase transformations in a Zn-22wt%Al-2wt%Cu alloy by XRD, SEM, TEM and FIM, Journal of Alloys and Compounds, 313 (2000).

DOI: 10.1016/s0925-8388(00)01206-8

[27] G. Texier, B. Oudot, C. Platteau, B. Ravat, F. Delaunay, Phase transformation in δ Pu alloys at low temperature: in situ dilatometric study, IOP Conf. Series Materials Science and Engineering 9 (2010) 1-8.

DOI: 10.1088/1757-899x/9/1/012033